From NBC's Mark Murray and Adam Verdugo
According to Karl Rove's new electoral map, Obama is leading McCain, 272-183 -- with 83 electoral votes in the toss-up category.

Note that the map is as of July 23, so it doesn't take into account the recent Quinnipiac polling in Colorado, Michigan, Minnesota, and Wisconsin. But per this map -- right now -- Obama could lose every toss-up state (Ohio, New Hampshire, Florida, Nevada) and still win the presidential election.